Mobile or self-propelled conveyor installations are known which can be advanced in a longitudinal direction and can be made to follow a partly curved course. This permits the installation to be towed by, or advanced up to, a mobile mineral mining or tunnel driving machine. A curved profile, particularly one with an S-shaped section, is necessary where the conveyor installation is transferring material between parallel roadways as in "board-and Pillar" mining. Normally such conveyor installations employ a scraper-chain conveyor or a belt conveyor which is guided longitudinally. For example, an installation described in DE-PS 3,241,129 employs a scraper chain conveyor with a number of pans disposed end to end and along which a scraper-chain assembly is circulated in upper and lower runs in the well known manner. The conveyor is driven by a number of drive stations distributed therealong. To effect the longitudinal displacement of the conveyor, the conveyor is first lowered with hydraulic appliances until the assembly rests on the floor. The pans are then displaced along the assembly with the latter acting, like an undercarriage, as a supportive abutment. In order to enable the conveyor to negotiate curves, it is better to utilise a guide which is to be laid on the floor manually to provide guidance and support for the entire conveyor. The guide can be composed of straight and curved sections laid down in front of the conveyor in the manner of a railway track. Sections can be removed from behind the conveyor and re-installed at the front from time to time as the conveyor advances to follow up the progress of the cutting machine. This system requires considerable labour and while the conveyor is being moved forwards the conveying work must cease. These stoppages slow up the working progress.
Another installation, known from DE-OS 3,733,032, has a conveyor which can be operated continuously even during its advancement longitudinally. In this installation the conveyor is a belt-type conveyor with a flexible belt equipped with driven tracks engaging on the floor. This construction is not particularly adaptable and is costly.
A general object of the present invention is to provide an improved form of mobile conveyor installation which is longitudinally displaceable and able to adopt curved or linear paths without undue difficulty.